IXTESriXA L SCHISTOSOMIA SIS 



267 



The anaemia is more severe than that 

 caused by T. sohum. 



The parasite is said to be more diffi- 

 cult to kill. 



It is common in Great Britain. 



It has no rostellum and no booklets. 



The uterus has 20 to< 30 lateral pro- 



a, oncosphere, in its radially 





cesses on either side, but these do not -striated embryophore (erroneously 



termed egg-shell) of Taenia afncaiia. 



again branch as in T. solium. Ikeatly magnified. (After von Lin- 

 Ac man^' 5,« -^c^n immafiirp mrpsitp'; ''^"^-^ -5, freed oncosphere of Z)^>j/?- 

 AS man\ as ^OO immature parasites ^^.^^^^^ caninum. (After Grassi and 



have been found in one pound of the Rovelli.) Both oncospheres show six 



• - pines. 



psoas muscle of an intected beast. 



ECHINOCOCCUS GRANULOSUS. 



This causes the cystic form of hydatid 

 disease. 



Hydatid disease has been known since the 

 days of Hippocrates. 



The cysticercoivi form only occurs in man. 



DISTRIBUTION. 



In Iceland, Australia, Europe, and Xew 

 Zealand; rarely in India and South Africa. 

 Egypt and the Philippines. 



The adult lives in the intestine of dogs, 

 jackals, and wolves. 



The cvsticercus lives in man, sheep, ox, 

 and pig. 



MORPHOLOGY. 



It is about 2 '5 to 6 mm. long. It has a 

 scolex and three segments. 



The last proglottis, when mature, equals 

 all the others in size. 



The scolex has four suckers. The rostel- 

 lum has a double row of twenty-eight to tift}- 

 hooks. The genital pore is alternate. 



The mature uterus has only lateral pro- 

 tuberances, the eggs ma\' form in heaps. 



THE LIFE CYCLE. 



Man is infected with the onchospheres 

 when petting a .dog, or by ingesting con- 

 taminated food. From the stomach the para- 



7\cnia echinococciis : the cirrus 

 sac, the vagina, uterus, ovary, 

 shell gland and vitellariuni, and 

 the testicles at the sides are 

 recognizihle in the second 

 proglottis; the posterior prog- 

 lottis shows the uterus partly 

 filled with eggs, as well as the 

 cirrus sac and the vagina. 50 i. 



